"Sthir Sukham Asanam" -- I (46,2 Patanjal Yoga Sutra)
"In which posture you get Stability and Comfort-is-Asana". In other words we can say,"Whatever is the posture,if the posture is comfortable and gives stability to practice next step,then,irrespective of posture, the posture it-self is called as "Asana".
The Asanas or Postures are as many as number of species of living creatures in this universe. Lord Siva has described 84,00,000 of Asanas . Among them 84 are best and among these, 32 are very useful.The Hatha Yoga Pradipika describes only sixteen asanas, and there are 32 asanas mentioned in the Gheranda Samhita.
Ordinary physical exercises develops superficial muscles of body only. Asanas are not just physical exercises; they have Biochemical, Physiological and Spiritual effects. Patanjali maharshi, too states that, perfection in asanas brings coordination between body, mind and soul. Asanas increases flow of life-force and restore it to its optimum level. Asanas remove obstacles in bloodvessels, nerves and make all the internal organs free for passage of their corresponding contents.Apart from this physical advantage facilitation,asanas makes internal organs healthier;and by removing obstacles makes the Life Force to flow easily and uninterruptedly. Yogis were searching for natural remedies to combat general health problems and ageing problems. In their search, they discovered & formulated hundreds of asanas, which can increase and restore the life force to its optimum level.
Four Asanas are prescribed for the purpose of Japa and meditation. They are Padmasana, Siddhasana, Svastikasana and Sukhasana. You must be able to sit in any one of these four Asanas at a stretch for a specific period without giving any stess to the body. Then only you will get Asana-Jaya, mastery over the Asana.Select any one Asana and achieve steadiness and perfection by repeated attempts.The steadier you are in your Asana, the more you will be able to concentrate and make your mind one-pointed. You must become as a living statue when you sit for Dhyana. Asana gives Dridhata (strength). Mudra gives Sthirata (steadiness). Pratyahara gives Dhairya (boldness). Pranayama gives Laghima (lightness). Dhyana gives Pratyakshatva (perception) of Self and Samadhi gives Kaivalya.
There are some Asanas which can be practised while standing like Tadasana, Trikonasana, Garudasana, etc. There are some which must be practised by sitting, such as Padmasana, Paschimottanasana etc. Some Asanas must be performed in lying position,like, Uttanapadasana, Pavanamuktasana, etc. Sirshasana etc., are done with head downwards and legs upwards.So, asanas can be classified as sitting postures,standing postures,lying postures.Basing on this classification sadhak should select a set of postures for regular practice,as per the need of his physical & physiological conditions.
A glass of fresh water should be taken before performing asanas. The stomach should be empty. Asanas can be performed 4 hours after a meal, half an hours after a glass of milk.When you sit in the Asana, keep your head, neck and trunk in one straight line,as erect as possible.This is a common precaution,which must be practiced in every asana. Whenver you feel body is overstressed, immediately perform Savasana and relax the body.
A Note on Physiology Of Asanas :
When the practicer assumes an ansana or a posture, his body will attain an unusual posture.When practicer retainsthis shape or posture for a specific period all the parts of body (ex., Spine,Shoulders,Knees) ,which has obtained a new posture will get a little more pressure on corresponding muscles.Blood flow and Oxuygen supply will be incresed to that corresponding muscles and nerves.Due to of this extra supply of Blood & Oxygen, Health&Hygiene of that corresponding muscle will be allways better than before practice.
So, the regular practice of particular Asana or 'Conmbination' will never allows that corresponding muscles to fall sick.( ex.,Regular Pranayamam practicers will become immune to Dust Allergy.)
Hence, Sadhaks has to choose 'a set of asanas' or 'a specific combination',which can keep the body in alert and active status from one session of practice to another session of practice.
In specific cases like practice against Digestive problems or Practice against pneumonia or lung problems,Cancer,AIDS etc.,will need specific 'Combination' and that must be practiced specially and carefully under guindence.